#include<stdio.h>
#define ABS(x) (x)<0?(-x):(x)
#define Max(a,b)  (a>b)?(a):(b)
void Swap(int* a,int* b)
{
    int c=*a;
    *a=*b;
    *b=c;
}


int main()
{
    int a=1,b=2;
    int* ptr_a=&a;
    int* ptr_b=&b;

    Swap(ptr_a,ptr_b);
    // Swap(&a,&b);
    printf("a:%d b:%d\n",a,b);

    int x;
    x = Max(10081,2);
    printf("the maxest is: %d",x);
}